The enhanced electro/photocatalytic activity for nitric oxide reduction to ammonia by B@g-C9N10 monolayer

Selective electro/photocatalytic reduction of nitride oxide (NO) to ammonia (NH3) provides a promising way to remove the pollutant under ambient conditions. The key to NO reduction reaction (NORR) is to develop more economical and efficient electrocatalysts compared to the industrialized Pt -based catalysts. In this work, the boron atom doping g-C9N10 monolayer (B@g-C9N10) is designed and the electro/photocatalytic NORR performance is systematically investigated by means of density functional theory (DFT). Among the N -end, O -end and side -on structures, the N -end NO adsorption is found to be the most stable one, which greatly favors the NO activation by the "a -donation and pi* back -donation" mechanism. Among the N -distal, N -alternating, O -distal, Oalternating, Mixed 1-3 hydrogenation pathways in the electrocatalytic process, the O -alternating and Mixed -2 pathways are the most efficient NORR routes, which have the same limiting potential (UL) of -0.386 V in the step of *NH2 ->*NH3. However, the NO molecule is more easily activated in *N-OH along O -alternating pathway than Mixed -2 pathway. The energy barrier can be further decreased by considering the implicit and explicit solvation model and the NH3 selectivity of B@g-C9N10 is higher than N2O, N2 and H2. The irradiating energy of 1.094 eV can decrease the reaction energy, resulting in the spontaneous NORR process along Mixed -2 pathway. Our findings uncover a promising approach to design a bifunctional NORR electro/photocatalyst with high NH3 selectivity and activity NO -> NH3 conversion.